JPS61287777A - Ink ribbon cassette - Google Patents

Abstract

PURPOSE:To prevent a cassette from being statically electrified, by providing guide pins formed of a conductive material on a carriage of a printer, and fitting the guide pins into an opening provided in a bottom surface of a cassette casing to thereby position the cassette on the carriage. CONSTITUTION:A printing head 13 is inserted into a recess 7 of the cassette casing 2, a ribbon-driving shaft 12 is engaged to a take-up reel 5, and the opening of the bottom surface of the casing 2 inclusive of an opening or notch of a conductive sheet is fitted to two guide pins 14 provided on the carriage 10, thereby mounting the ink ribbon cassette 1 on the carriage 10. Even when the interior of the cassette 1 is statically electrified to a high voltage due to friction between the head 13 and an ink ribbon 6 or due to friction between the casing 2 and the reels 4, 5, the static charges can be discharged to the exterior through the guide pins 14 formed of a conductive material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to the structure of an ink ribbon cassette mounting section used in a thermal transfer printer, wire dot printer, typewriter, or the like.

[Prior art]

Recording devices such as printers and facsimiles, as well as typewriters, have an ink ribbon cassette mounted on a carriage that moves along the paper, and are configured to transfer ink while feeding the ink ribbon between the print head and the paper. There is.

The ink ribbon cassette includes a supply reel and a take-up reel in a cassette case, and is configured to feed the ink ribbon through a printing stent V insertion portion during printing operations. The cassette case is closed with a cassette lid.

Incidentally, the cassette case and the cassette lid are generally made of a non-conductive material such as plastic, and the cassette, ink ribbon, etc. are charged with electricity during the printing operation for the following reasons.

i) Friction between the print head and the ink ribbon ii) Friction between the cassette case and each reel 111) Friction between the cassette case and the ink ribbon iv) Process of transferring ink to paper ■) The ink ribbon is peeled off from the supply reel The following problems occur due to these processes.

i) The user touches the cassette and receives an electric shock.

ii) Signals from the CPU may be disturbed due to charging of the cassette, resulting in malfunction.

iii) Electronic elements such as the CPU may be damaged due to charging of the cassette.

Therefore, as a countermeasure, there is a method of installing a static elimination brush.
This method has problems with appearance treatment, and also increases the size and cost of the device.

There is also a method of adding a ground wire, a capacitor, or a shield plate to the control circuit, but this method also results in a complicated and large circuit configuration, which increases the cost.

〔the purpose〕

An object of the present invention is to solve these conventional problems and to prevent the ink ribbon cassette from being charged with a simple and inexpensive method.

[Overview] The present invention achieves the above object by providing a guide pin made of a conductive material on a carriage, and positioning the guide pin on the carriage by fitting the guide pin into an opening in the bottom of a cassette case.

〔Example〕

The present invention will be described in detail below with reference to the drawings.

Fig. 1 shows an embodiment in which the present invention is applied to an ink ribbon cassette of a thermal transfer recording device, Fig. 2 shows the cassette case in Fig. 1, and Fig. 3 shows the line ■-■ in Fig. 2. Each cross section is shown.

In FIG. 1, an ink ribbon cassette 1 has a housing consisting of a cassette case 2 and a cassette lid 3. A supply reel 4 and a take-up reel 5 are pivotally supported within the cassette case, and an ink ribbon 6 on the supply reel is supported. It is configured to be wound onto a take-up reel 5. A recess 7 for inserting a print head (a thermal head in the illustrated example) is formed on the front side of the cassette case 2, and the ink ribbon 6 is guided to pass through this recess.

The carriage 10 is guided and supported on a guide shaft 11,
The ribbon drive shaft 12 rotates in synchronization with the movement of the carriage, which is driven reciprocally in the direction of arrow A by a stepping motor or the like.

A print head 13 is mounted on the front side of the carriage 10.

The ink ribbon cassette 1 is mounted on the upper surface of a carriage 10, and two guide pins 14 and 14 are provided on the upper surface of the carriage 10 for positioning the cassette 1.
has been planted. Furthermore, a leaf spring 15 is provided at the rear of the upper surface of the carriage 10 for detachably mounting the cassette 1 thereon.

FIG. 2 shows the state of the cassette case 2 with the cassette lid 3 and ribbon 6 removed when the cassette 1 is installed, that is, the state of the cassette case 2 when it is installed. Further, FIG. 3 shows a cross section taken along the line ■--■ in FIG. 2 when the cassette 1 is installed.

1 to 3, a conductive sheet 16 is laid between the bottom surface of the cassette case 2, that is, the inner surface of the cassette case 2, and the ink ribbon 6. As shown in FIGS. Further, a fitting opening 17.17 (FIG. 3) is formed on the bottom surface of the cassette case 2 at a position corresponding to the guide pin 14.14. In the illustrated example, the conductive sheet 16 is laid in a range that covers the opening 17.17, and therefore this conductive sheet also has an opening or notch for fitting the guide pin 14.14. There is.

As the conductive sheet 16, metal foil, metal particles, or a plastic sheet mixed with carbon can be used.This conductive sheet not only prevents static electricity but also improves the slippage when the ink ribbon 6 comes into contact with the ink ribbon. The function is to maintain smooth running and guidance of the vehicle.

To install the ink ribbon cassette 1, insert the print head 13 into the recess 7, engage the ribbon drive shaft 12 with the take-up reel 5, and open the opening 17 of the cassette case 2.
17 (including the opening or notch in the conductive sheet 16) is fitted onto the guide pin 14.14 and is set by pressing against the spring force of the leaf spring 15. The cassette 1 can be easily removed by lifting it against the spring force of the leaf spring 15.

The guide pins 14.14 are therefore made of a conductive material such as metal or metal powder or carbon-containing plastic.

Furthermore, when the cassette 1 is mounted on the carriage 10, the guide pins 14.14 are in contact with the conductive sheet 16 inside the cassette case 2, as shown in FIGS. 2 and 3.

According to the above configuration, the guide pins 14, 14 are made of a conductive material, and the guide pins are thrust into the cassette case 2 when the cassette is installed, so that the print head 14, 14 during the printing operation
Even if static electricity is generated due to the above-mentioned causes such as friction between the ink ribbon 3 and the ink ribbon 6 or friction between the cassette case 2 and each reel 4. It can easily be discharged to the outside through pins 14.14.

In this way, charging inside the cassette 1 could be effectively prevented.

Further, since the conductive sheet 16 is laid inside the cassette case and the guide pins 14 and 14 are brought into contact with it, the antistatic effect inside the cassette 1 can be further improved.

The carriage 10 may be an insulator, but if it is made of a conductive material, such as metal or conductive plastic, the above-mentioned discharge effect can be further improved.

Furthermore, although two guide pins 14,14 are provided in the illustrated structure, the number and arrangement of the guide pins can be set as appropriate.

〔effect〕

As is clear from the above description, according to the present invention, the static electricity generated in the ink ribbon cassette due to the printing operation can be easily released to the outside, and charging of the cassette can be reliably prevented.

[Brief explanation of the drawing]

1 is an exploded perspective view showing an ink ribbon cassette according to an embodiment of the present invention together with a carriage, FIG. 2 is a plan view of the cassette case shown in FIG. Line I[[-H in Fig. 2 when installed
FIG. 1 ------- Ink ribbon cassette, 2...
- Sesoto case, 6--- Ink ribbon, 10
-------- Carriage, 14-=・-Guide pin, 16
-... Conductive sheet.

Claims (2)

[Claims] (1) An ink ribbon cassette characterized in that a guide pin made of a conductive material is provided on the carriage, and the guide pin is fitted into an opening in the bottom of the cassette case to position it on the carriage. (2) The ink ribbon cassette according to claim 1, wherein a conductive sheet is provided between the inner surface of the cassette case and the ink ribbon, and the guide pin is brought into contact with the conductive sheet.